EnergyBalanceinMotion_人人文库网

来自 : www.renrendoc.com/p-218535...h 发布时间：2021-03-25

SpringerBriefs in Physiology For further volumes: Klaas R. Westerterp 1 3 Energy Balance in Motion Klaas R. Westerterp Department of Human Biology Maastricht University Maastricht The Netherlands © The Author(s) 2013 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. Exempted from this legal reservation are brief excerpts in connection with reviews or scholarly analysis or material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Duplication of this publication or parts thereof is permitted only under the provisions of the Copyright Law of the Publisher’s location, in its current version, and permission for use must always be obtained from Springer. Permissions for use may be obtained through RightsLink at the Copyright Clearance Center. Violations are liable to prosecution under the respective Copyright Law. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. While the advice and information in this book are believed to be true and accurate at the date of publication, neither the authors nor the editors nor the publisher can accept any legal responsibility for any errors or omissions that may be made. The publisher makes no warranty, express or implied, with respect to the material contained herein. Printed on acid-free paper Springer is part of Springer Science+Business Media ( ) ISSN 2192-9866 ISSN 2192-9874 (electronic) ISBN 978-3-642-34626-2 ISBN 978-3-642-34627-9 (eBook) DOI 10.1007/978-3-642-34627-9 Springer Heidelberg New York Dordrecht London Library of Congress Control Number: 2012953017 v Man survives in an environment with a variable food supply. Energy balance is maintained by adapting energy intake to changes in energy expenditure and vice versa. Human energetics is introduced using an animal energetics model including growth efficiency, endurance capacity and adaptation to starvation. Animal energet- ics was the starting point for assessment of energy expenditure with respirometry and doubly labelled water and of body composition with densitometry and hydrometry. Examples of endurance performance in athletes and non-athletes illustrate limits in energy expenditure. There is a complicated interaction between physical activity and body weight. Body movement requires energy as produced by muscles. Thus, there is an interaction between physical activity, body weight, body composition and energy expenditure. Overweight is caused by energy intake exceeding energy expenditure. The questions of how energy intake and energy expenditure adapt to each other are dealt with. The evidence presented, originating from fundamental research, is translational to food production and to physical activity-induced energy expenditure in competitive sports. Another obvious and relevant clinical application deals with overweight and obesity, with the increasing risk of developing diabetes, cardiovascular disease and cancer. Finally, activity induced energy expenditure of modern man is put in perspective by compiling changes in activity energy expendi- ture, as derived from total energy expenditure and resting energy expenditure, over time. In addition, levels of activity energy expenditure in modern Western societies are compared with those from third world countries mirroring the physical activ- ity energy expenditure in Western societies in the past. Levels of physical activity expenditure of modern humans are compared with those of wild terrestrial mam- mals as well, taking into account body size and temperature effects. Taken together this book shows how energy balance has been in motion over the past four decades. Preface vii Dr. Klaas R. Westerterp is professor of Human Energetics in the Faculty of Health, Medicine and Life Sciences at Maastricht University, The Netherlands. His M.Sc in Biology at the University of Groningen resulted in a thesis titled ‘The energy budget of the nesting Starling, a field study’. He received a grant from the Netherlands Organisation for Scientific Research (FUNGO, NWO) for his doctorate research in the Faculty of Mathematics and Natural Sciences at the University of Groningen. His Ph.D. thesis was titled ‘How rats economize, energy loss in starva- tion’. Subsequently, he performed a three-year post- doc at Stirling University in Scotland supported by a grant from the Natural Environment Research Council (NERC), and a two-year postdoc at the University of Groningen and the Netherlands Institute of Ecology (NIOO, KNAW) with a grant from the Netherlands Organisation for Scientific Research (BION, NWO) in order to work on flight ener- getics in birds. In 1982, he became senior lecturer and subsequently full professor at Maastricht University in the Department of Human Biology. Here, his field of expertise is energy metabolism, physical activity, food intake and body composition and energy balance under controlled conditions and in daily life. He was editor in chief of the Proceedings of the Nutrition Society and he is currently a member of the Editorial Board of the journal Nutrition and Metabolism (London) and of the European Journal of Clinical Nutrition, and editor in chief of the European Journal of Applied Physiology. About the Author ix The content of this book is based on work performed with many students and colleagues as reflected in the references. Paul Schoffelen and Loek Wouters tech- nically supported measurements on energy expenditure with respirometry and doubly labelled water. Margriet Westerterp-Plantenga reviewed the subsequent drafts of the manuscript. Louis Foster edited the final text. Acknowledgments xi 1 Introduction, Energy Balance in Animals . . . . . . . . . . . . . . . . . . . . . . . 1 2 Energy Balance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 3 Limits in Energy Expenditure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 4 Energy Expenditure, Physical Activity, Body Weight and Body Composition. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 5 Extremes in Energy Intake . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 6 Body Weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71 7 Growth, Growth Efficiency and Ageing. . . . . . . . . . . . . . . . . . . . . . . . . 83 8 Modern Man in Line with Wild Mammals . . . . . . . . . . . . . . . . . . . . . . 91 Appendix. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101 References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111 Contents xiii ADMR Average daily metabolic rate AEE Activity-induced energy expenditure ATP Adenosine triphosphate BMI Body mass index BMR Basal metabolic rate COPD Chronic obstructive pulmonary disease DEE Diet-induced energy expenditure DEXA Dual energy X-ray absorptiometry for the measurement of body components like mineral mass EE Energy expenditure EG Energy deposited in the body during growth EI Energy intake FAO Food and agriculture organisation of the United Nations FFM Fat-free body mass FM Fat mass of the body SMR Sleeping metabolic rate TEE Total energy expenditure Tracmor Triaxial accelerometer for movement registration UNU United Nations University WHO World Health Organization Abbreviations 1 Abstract Man is an omnivore and originally met energy requirements by hunt- ing and gathering. Man evolved in an environment of feast and famine: there were periods with either a positive or negative energy balance. As an introduction to human energetics, this book on energy balance in motion starts with a chapter on animal energetics. How do animals survive and reproduce in an environment with a variable food supply? The examples on animal energetics illustrate how animals grow, reproduce and survive periods of starvation. It is an introduction to method- ology and basic concepts in energetics. Growth efficiency of a wild bird in its nat- ural environment, here the Starling, is similar to a farm animal like the Domestic Fowl. Reproductive capacity is set by foraging capacity, determined by food avail- ability and the capacity parents can produce food to the offspring. Birds feeding nestlings reach an energy ceiling where daily energy expenditure is four times resting energy expenditure. Starvation leads to a decrease in energy expenditure, where the largest saving on energy expenditure can be ascribed to a decrease in activity energy expenditure. Keywords Activity factor • Body temperature • Doubly labelled water method • Energy ceiling • Gross energy intake • Growth efficiency • Metabolizable energy • Starvation The Energy Budget of the Nestling Starling From the late Middle Ages, nestling Starlings were harvested to prepare paté or soup. As such, Starlings were a source of animal protein in a hunter and gatherer system. Passerine birds have short incubation periods (12–14 days) and a nestling period of some weeks, characterized by rapid growth. The conversion ratio of food to energy incorporated in the growing body is high. Here the energy budget of the nestling Starling is presented for the calculation of the growth efficiency of a wild animal in its natural environment. The result is compared with figures for the Domestic Fowl, one of our current sources for animal protein. In the Netherlands, wild Starlings were offered artificial nest sites by mount- ing ‘Starling pots’ against a building (Fig. 1.1). Pots were made from clay with a Introduction, Energy Balance in Animals Chapter 1 K. R. Westerterp, Energy Balance in Motion, SpringerBriefs in Physiology, DOI: 10.1007/978-3-642-34627-9_1, © The Author(s) 2013 21 Introduction, Energy Balance in Animals long neck, and a hole 5 cm in diameter as entrance. Pots were mounted against the wall of a house at a height of some meters with the neck horizontal. At the back, against the wall, was a hole to harvest the chicks. The optimal harvest time is just before fledging, in the third week after the eggs hatch. An average brood provides four to five chicks of 70 g each or about 300 g Starling. Starlings prefer to breed in colonies. Thus, one can mount several pots on the same house. Additionally, Starlings often start a second brood, especially when taking the chicks disturbs the first brood. The Starling (Sturnus vulgaris) is a feasible subject for a field investigation. As a hole nester readily accepting nest-boxes, a Starling colony can be founded at any convenient point bounding on pastureland for foraging. The nestlings develop from hatching to fledging in 19–21 days. There is close synchrony in breeding behaviour within the colony and the adults forage in the same general area allow- ing several adults to be observed at the same time, thus duplicating observations. Growth efficiency, the relation between energy intake and the energy deposited in the body during growth, is assessed by measurement of the separate components of Fig. 1.1 Five ‘Starling pots’, mounted against the front of a house or pub, with somebody inspecting from the loft (Etching Claes Janz Visscher. The village party, 1617. With permission: Rijksmuseum, Amsterdam) 3 the energy budget: food intake, rejecta, metabolizable energy, energy expenditure, and energy stored in growth (Fig. 1.2). Food provides the organism with energy for maintenance, temperature regulation activity and growth. Of the total incoming food energy or gross energy, a part is voided as rejecta including both faeces and urine. The remainder is commonly termed metabolizable energy. Measurements of the separate components of the energy budget of the nestling Starling are described to illustrate the methodology and general principles of energetics (Westerterp 1973). Energy intake of the nestlings is measured by taking samples of the meals, and by counting the total number of meals per day. Meals can be sampled by the col- lar method. Nestlings are collared with a cotton thread around the neck preventing swallowing of a meal after feeding. Meals are removed after each parental visit for later analysis with regard to diet composition and energy content. Depending on age, nestlings can be collared for periods of one to three hours, between some hours after sunrise and before sunset so as not to interfere with the very first and last feedings of the day. The feeding frequency can be determined by automatic counting of parental visits with an electric contact in the nest entrance. Energy output in rejecta is measured by taking samples of rejecta, and by observing the production frequency of rejecta. Faeces and urine are excreted together in mem- branous sacs, an adaptation enabling the parents to remove them and thus keeping the nest clean. The collection of samples is a simple matter, especially after the fifth day when the nestlings automatically produce a faecal sac when handled. The frequency of faecal sac production is determined by watching the parents as they carry off the glistening white faecal sacs from the nest. The energy content of food and faecal samples is determined by bomb calorimetry. The first days after hatching, chicks are fed with spiders; subsequently: leather- jackets (Tipula paludosa), earthworms (Lumbricidae), and beetle species comprise Fig. 1.2 Diagrammatic representation of the energy budget of a nestling Starling (After Wester- terp 1973) The Energy Budget of the Nestling Starling 41 Introduction, Energy Balance in Animals the main dietary components. Spiders provide some 80 % metabolizable energy; whereas, leatherjackets, worms and beetles provide only 60 % metabolizable energy. However, Starlings cannot manage to provide sufficient high quality food like spiders to meet the increasing energy requirement of growing chicks. A three- day chick weighs 20 g and consumes 14 g food per day. After two weeks, body weight and food intake is tripled. To meet the energy requirement of a brood of four or five chicks, the parents together collect daily some 200 g of leatherjackets, earthworms and beetles. Additionally, they have to meet their own energy require- ment. Nestling feeding parents have to work at their upper limit. As shown in Chap. 3, they perform at a similar level as one of the most demanding endurance performances in man: the Tour de France. Metabolizable energy, gross energy intake corrected for energy loss in rejecta, is available for body maintenance, for maintaining body temperature, physical activity and growth. After hatching, chicks are brooded nearly con- stantly by one of the parents, but after a week this only happens overnight. Then, parents are both foraging from sunrise to sunset and the growing chicks get more physically active in the nest. Thus initially, 50 % of the metabolizable energy goes to growth. This fraction decreases to zero just before fledging. Over the total interval from hatching to fledging, 22 % of the metabolizable energy is converted to growth, in this case in Starling. This is equivalent to 14 % of the total or gross energy intake. This is similar to that of 16 % for Domestic Fowl. Growth efficiency, the relation between energy intake and the energy depos- ited in the body during growth, does not depend on the pattern of ontogeny but seems rather a function of the type of food. Higher figures are reported for fish- eating birds. Natural selection favours individuals producing the optimal number of fertile offspring. Starlings habitually lay a clutch of three to seven eggs. The figures as presented above were mainly from nests with four chicks. The question is whether the production of offspring is higher for a larger brood size. Is the food require- ment of a chick in a larger brood lower than in a smaller brood? The higher return in a larger brood could be a reflection of the reduced energy requirement for maintaining body temperature through huddling. Comparative observations in broods ranging in size from three to seven chicks showed food intake per gram of growth to be optimal for a brood of five (Fig. 1.3). A chick in a brood of five needs 10–20 % less energy to reach a given body weight at fledging than in a brood of three, a saving probably mainly based on huddling behaviour. This trend does not continue with a further increase to brood size seven. Here a chick needed 5–10 % more energy. Deterioration of the insulative properties of the nest in the big- gest broods might explain this. Additionally, chicks in bigger broods spend more energy in activity competing for food. Parents of big broods have to collect more food and tend to spend less time in nest sanitation. They bring in a higher pro- portion of leatherjackets and earthworms with higher water content, causing thin rejecta, which are difficult to remove. In conclusion, growth efficiency of a wild Starling in its natural environment is similar to a farm animal like the Domestic Fowl. 5 Foraging Limits in Free Ranging Birds The number of offspring a bird can produce is mainly a function of food availabil- ity and foraging capacity. In the Starling it was the availability of spiders, leath- erjackets, earthworms and beetles, and how much a bird can collect to feed the nestlings. Additionally the parent has to meet its own energy requirement for the activity by foraging. The most energy demanding activity in this situation is flying up and down between the foraging grounds and the nest. Thus, the main determi- nant for breeding success of the chicks is the working capacity of the parents. As mentioned before, nestling feeding parents reach a ceiling that caps the energetic effort an animal or human can maintain over a timeframe of days or weeks. This led to the question how to measure energy expenditure in free ranging animals. The method of choice was the doubly labelled water method. The method was invented in 1955, was validated in laboratory rats and got its first field applica- tion in birds like racing pigeons during long distance flights. It subsequently was applied for the measurement of energy expenditure in man under daily living con- ditions. Nowadays, it is the gold standard for the assessment of energy require- ment of modern man. Presented evidence in this book on energy balance in motion is largely based on studies where energy expenditure and physical activity is quan- tified with doubly labelled water. The doubly labelled water method for the measurement of energy expenditure is based on the discovery that oxygen in the respiratory carbon dioxide is in iso- topic equilibrium with the oxygen in body water. The technique involves enrich- ing the body water of an animal with an isotope of oxygen and an isotope of Fig. 1.3 Food intake per gram growth of a nestling Starling in relation to brood size (After Westerterp et al. 1982) Foraging Limits in Free Ranging Birds 61 Introduction, Energy Balance in Animals hydrogen and then determining the washout kinetics of both isotopes. Most of the oxygen isotope in a labelled animal is lost as 展开阅读全文